Radio Rocket

Check out the Radio Rocket Tag for blog posts about this project or Follow the Rocket’s Adventures on Mastodon!

N3VEM Radio Rocket

I’m currently dabbling with some rocketry stuff with the kiddos, so of course I had to start playing around with ways to stick some radio stuff in the rockets.

Upcoming Launches

June 13th / 14th

We’re targeting Launch #2 of Ponzu to occur June 13th or 14th depending on weather. That date may move forward or backwards as the time approaches and we can get a better look via shorter-term weather forecasts.

Launch number 2 will be ‘simpler’ from a technology standpoint, because we built a new ground station, and will want to keep things more basic to eliminate extra variables in the launch muddying the waters of our data collection. It will be a LoRa only flight, and we probably won’t be doing any live-posting of telemetry, as there is some additional work to do with our data uplink via AREDN before we’ll be ready for that. This should however, be our highest Radio-Rocket launch to-date, so if you have a way to receive 70cm LoRa, you should be able to receive some of our packets from pretty much anywhere in Lancaster County, and might be able to receive some from high points in Berks County, Chester County, Delaware County, York County, Lebanon County, Dauphin County, and potentially into parts of north east Maryland (Parts of Baltimore County, Harford County, Cecil County, and maybe Kent County a little bit).

Motor: G53FJ
Launch Weight:634g ; 22oz
Projected Altitude: 606m ; 1988ft
Estimated Max Velocity: 439kph ; 273mph Estimated Max Acceleration: 126m/s^2 ; 13g Estimated Flight Time: 126s

Radio Rocket Ponzu (v3)

Radio Rocket version 3 was officially announced with the name ‘Ponzu’ on September 28th 2023.

A skinny rocket

Height: 109.86cm ; 43.25” (+22.2cm ; +8.75” with payload extension for ESP32cam)

Diameter: 41.6mm ; 1.64” (BT-60 sized tube)

Launch Weight, w/o Motor: 487g ; 17.18oz (+95g ; +3.35oz with payload extension for ESP32cam)

Recovery: 30” parachute

Paint: Gold on the bottom 2/3, fading to blue with a spattered fade

Telemetry: GPS data via APRS packets (no digipeating) on 144.39MHz, and magnetometer, gyro, acceleration, barometric pressure, altitude, and messaging via LoRa on 434MHz. Flight data will also be posted live to Mastodon via the ground station’s ‘auto-tooter.’ Receipt of flight updates via XMPP are available upon request.

Check out my initial blog post detailing the beginnings of the Ponzu project here: Radio Rocket V3 Beginnings.

The versions of the radio rocket project are becoming more polished as we go. The major change in the electronics for Ponzu is that, after some encouragement by certain members of the Ham Radio Workbench Crew, we are moving away from the ‘breakout boards glued to a piece of wood’ construction, and have moved to custom designed PCB carriers. We’re still using a lot of breakout boards, but now instead of wires running back and forth, the circuit boards are the sled, and contain all of the power and data buses, so there are no more wires flopping around.

A long skinny stack of circuit boards

The ground station is also getting an overhaul. The hardware is still the same as the previous versions, but there are now some algorithms running to convert raw gyro and magnetometer readings into Pitch, Heading, and Roll so that the data means something, instead of just being raw sensor readings. There have also been changes to the UI to get the most meaningful stuff up front, with some other items moved off the main screen. Oh, and we’ve gone fully metric - it makes the math so much easier…

A UI Dashboard displaying rocket Telemetry

And last but not least, is the actual rocket. Ponzu is based on an Apogee Components Kestrel Kit, but made 9 inches longer by replacing the stock 9” long payload bay with an 18” long payload bay.

Launch 1 report coming soon!

Radio Rocket Ohyō (v2)

Radio Rocket version 2 was christened ‘Ohyō’ on April 5th, 2023.

Ohyō had 3 flights - one without the electronics payload, two with the electronics payload. It was a blast, and we got a done of fun data!

A tall, skinny rocket

Height: 198cm ; 78”

Diameter: 38mm ; 1.5”

Weight, w/o Motor: 1,261g ; 44.5oz

Recovery: dual 30” parachutes

Paint: Yellow and Green, inspired by vintage RF spectrum analyzer traces

Telemetry: GPS data via APRS packets (no digipeating) on 144.39MHz, and magnetometer, gyro, acceleration, barometric pressure, altitude, and messaging via LoRa on 433MHz. Flight data will also be posted live to Mastodon via the ground station’s ‘auto-tooter.’

Launch 1 Report
Launch 2 Report
Launch 3 Report coming eventually, if at all :-P The tldr; is that the data and electronics worked great, but the rocket crashed. Luckily all the electronics survived the crash, and are now getting rebuilt into the system for version 3 of the radio rocket!

Radio Rocket Nigemono (v1)

Version 1 of the radio rocket, was named Nigemono posthumously

Radio Rocket

It was a modified mid-power Aerotech Initiator Kit, made longer to accommodate the electronics and antenna’s, and equipped with a larger than stock parachute because of the extra weight associated with the extra components. We crashed that one…

The Electronics Sled

The lead picture is of the electronics sled that was built for Ohyō, that slides into the rocket. This carries the LoRa radio and sensors for telemetry. The APRS radio is on it’s own sled, which is closer to the nose of the rocket.


Nigemono (v1) had a lightAPRS for APRS packets. I detailed in the lightAPRS groups.io group the modifications that I did so that I could get more packets through faster, since at the relatively low altitudes this rocket will reach, the flights will be short. Ohyō uses the very similar, but slightly different lightAPRS W-2.0.


Onboard Ohyō is a Teensy 4.1 with a 70cm LoRa module and some other sensors. The LoRa radio allows the rocket to send telemetry data, and also receive some basic commands from the ground station, along with acting as a LoRa message repeater.

Ground Station

To communicate with the rocket, the current ground station is based on a Libre Computer LePotato single board computer, and a 70cm Adafruit Feather w/ LoRa, as the companion radio to the LoRa module on the rocket. It also contains an SDR dongle for receiving the APRS packets, and runs both a node-red server and packet modem server to share this data with other connected devices in the field (tablet, phone, laptop, etc.)

Follow the Radio Rocket on Mastodon!